Closure



July 31, 1962 E. A. wlLcKENs 3,047,176

CLOSURE l Filed March 29, 1956 Flc. 1.

INV ENTOR wwf/m# www ATTORNEY United States Patent 3,047,176 CLOSUREEibe A. Wilckens, Baltimore, Md., assignor to Crown Cork & Seal Company,Inc., Baltimore, Md., a corporation of New York Filed Mar. 29, 1956,Ser. No. 574,658 1 Claim. (Cl. 215-40) This invention relates to caps ofthe crown type and more particularly to an improved liner for said caps.

A primary object of this invention is theI provision of a crown type caphaving improved sealing ability.

Another object of this invention is the provision of a crown cap havingan improved liner which enables better sealing of chipped bottles.

Other objects and advantages of the present invention will be in partobvious and in part explained by reference to the accompanyingspecification and drawings.

FIGURE 1 is a cross sectional view of a cap formed in accordance withthe present invention;

lFIGURE 2 is a cross sectional view of a liner in accordance with thepresent invention; and FIGURE 3 is a cross sectional view illustratingthe present invention as applied to a container.

Referring more specifically to the drawings, there is shown a crown typecap or closure having a top or end plate 12 and `a marginal skirt 14having flutes or depressions 16 alternating with rib yforming plates 18.

Cap 10 has a liner or gasket 20 of an elastic or preferably plasticsealing material, which is of unitary construction, and comprises yarelatively thin web portion 22, preferably of uniform thickness, aperipheral web portion 24 of substantially the same thickness as webportion 22, and a relatively thick boss 26 which is formed between thetwo previously mentioned web portions.

Boss 26 is non-symmetrically formed, the apex 28 being radially disposednearer the outer side of said boss. Since apex 28 is not centrallylocated, the outer side 30, of boss 26, has a much greater, or steeper,mean slope than does the inner side 32; the slope being measured withrespect to the plane of the web. The disclosed and preferred shape ofboss 26 is instrumental in effecting tight sealing engagement with acontainer since it permits conformation of the seal to the container topwithout the exertion of unduly high sealing pressures thereon.

The peripheral web portion 24, which completely surrounds boss 26 iscurved in such a manner that it readily conforms to that portion of theinner surface of cap 10 between top '12 and skirt 14. By curvingperipheral portion 24 in the same direction as boss 26 an annularchannel or groove 34 is created which provides space for the expansionor altered location of boss 26 when the cap is secured to the container.Additionally, since the lower edge 36 of peripheralr portion 24 conformsto the inner surface of cap 10, it is apparent that the repositioning ofthe material comprising boss 26 will cause an effective seal extendingfrom the lower edge 36 to substantially the inner edge of the boss. Sucha seal isv obviously of great commercial value in the sealing of chippedbottles where small portions of the locking ring are missing. The mannerin which liner 20 co-acts with a bottle locking ring is clearlyillustrated in FIGURE 3 where boss 26 is shown in position againstlocking ring 38 of bottle 40.

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A typical example of a satisfactory plastisol composition is:

Parts Geon 1211 (polyvinyl chloride having -a molecular weight of about89,000) 60 Dioctyl phthalate (di-Z-ethylhexyl phthalate) 4 Calciumstearate 3 Staybelite No. 10 (glycerol ester of hydrogenated rosin) Inthe example all parts are by weight.

Among the advantages of the present cap and liner i design is the `factthat the top of the crown is brought as close as possible to the top ofthe glass. 'l`his permits a maximum reduction in the height of the Icapand in the size of the blank diameter. Thus there can be employed capshaving a height of only .200 inch and blank diameter need only be 1.406inch, in contrast to avcap of .257 height and a blank diameter of 1.5inch with conventional caps.

It is to be understood that various possible embodiments may be made ofthe mechanical features of the above invention, all without departingIfrom the scope thereof, and that all matter hereinbefore set forth orshown in the accompanying drawings is to be interpreted as illustrativeand not in a limiting sense.

I claim:

A plastic unitary sealing liner adapted for use with la container havinga cap of the crown type as a closure therefor, said sealing linercomprising a thin central web portion, -a peripheral web portion ofsubstantially the same thickness as said central web portion and acontinuous circular boss connecting said central web portion and saidperipheral web portion, said boss being inwardly spaced from the edge ofsaid liner and having a continuous rounded apex thereon, said apex ofsaid boss being eccentrically positioned with respect to a vertical lineextending through the center of said boss whereby the slope of the innersurface of said boss is substantially less than the slope of the outersurface of said boss, said peripheral web portion being curved and theouter edge thereof being in substantially the same plane as the top ofsaid boss.

References Cited in the iile of this patent UNITED STATES PATENTS2,427,699 Aronovsky et al. Sept. 23, 1947 2,543,775 Gora Mar. 6, 19512,654,913 Maier Oct. 13, 1953 2,681,742 Miller .Tune 22, 1954 2,684,774Aicllele Ju1y'27, I1954 2,739,724 Gora Mar. 27, 1956 2,754,276 Walker etal. July l0, 1956 FOREIGN PATENTS 523,527 Belgium Oct. 31, 1953

